Fertilizer mix to encourage fruit set

[IronPete]

Hi all;

I tried a few searches on here before writing this and don't think I found what I am looking for so I thought I would ask.

I started my tomatoes late this year and to make matters (maters?) a little worse we have a shade problem so I am not getting the full 8 hours of direct. That said most plants have flowers and some fruit started so things will be ok. Its those other, more stubborn plants that haven't started to produce many flowers. I thought I would run down to the store and get some bloom starting fertilizer but the mix wasn't what I expected. It was 15-30-15 which is the same as the ancient bucket of miracle grow in the back of the shed. I thought the last number was the one that pushed the flowering but apparently I may be mistaken. I have a bucket of some other "tomato food' that is 15-15-30. Would it work better? I started them with a CIL product specifically for tomatoes. I think it was a 12-12-24 and was slow release. After about 6 weeks I started adding a little fish emulsion once a week.

Which of these products would you recommend to get the flowering happening? If someone knows of a thread where these nitrogen-potassium-phosphorous and their effects are explained I would love to know so please post.

Hey Craig, maybe you and the TTF guy could get together and write a book about fertilizers for tomatoes. What, where and when! Now that would be a useful book!

Pete

[Gardeneer]

I think 15-30-15 is too high on "P". That is more like bloom booster for some flowers.
Most plants use more N an K than P. From what I have gathered tomatoes will do better with more K in flowering and fruiting stage.
Here in TV lot of gardener use Texas Tomato food which has 3.1 -3.8 -7 analysis for flowering and fruiting stage. As you can see K is almost twice as much as N and P.

At this time in the season you wouldn't want to grow too much foliage and even not too much flowers as they won't have a chance to become ripe fruits before the end on season in your location. Just my opinion.

Gardeneer.

[feldon30]

I like 3-4-6 or 4-7-10. The lower the first number (Nitrogen -- green leafy growth), the better.

You know, if you can't buy the fertilizer you want, it's not that hard to buy Bone Meal, Blood Meal, and other products to mix your own.

[IronPete]

They had a bonemeal/bloodmeal mix that looked like the analysis that Gardeneer mentioned for the TTF. I did plant several earlies that are almost ready but I don't have much hope for Northern Lights or Brandywine Yellow. The Cherokee purples are close too (those and Black cherry are the only 2 that have been in every garden I have grown since trying them for good reason). My Casey's Pure Yellows are really coming along now too.

Thanks for your input folks. An interesting topic to say the least!

Peter

[bower]

Iron Pete, I don't know what the soil is like in Texas, but I'm willing to bet it's nothing like mine. Much depends on your conditions, pH for one thing, and what's abundant in the soil already. Not sure where Coburg is or what soils, or your garden soil, are like.

But Phosphorus is the element needed for flowering and setting fruit, also promotes root growth. If it's limited, or if N is way more abundant, then you get a lot of foliage instead of flowers and fruit. N is the thing that makes for healthy foliage and rapid growth overall, including fruit growth once you get them set.

Potassium is important for fruit quality - it affects the sweetness of the fruit as they ripen. Also makes for strong sturdy stems afaik, but that may be more about the early season growth.

Fusion Power pointed out in another thread, that in cold soils, phosphorus tends to be limiting because the plants have trouble taking it up, so making sure P is available is important if the climate is on the colder side.... Personally I use a little bone meal in the pot for my seedlings, and I use a cup of bone meal in the planting hole for each one (as well as other amendments) to make sure that phosphorus is there for the flowers and set. Bone meal has some N but way more phosphorus. Seems to work for me. Also my seedlings have great roots - I have compared with other seedlings grown with fish emulsion - more N and less P - and they don't have the same early start on strong root systems afaict.

So if your problem is few flowers and fruit set at this stage, I would go with the fert with the higher number in the middle. Switch to a higher K formula when the fruit are set and growing on. MHO.

[Hellmanns]

Shoot them some N, then have K there to back it up.

[Worth1]

Originally Posted by Hellmanns

Shoot them some N, then have K there to back it up.

I totally agree.

I fertilize with something that is higher in N than anything else.
Best year ever.

Plant tone. 5-3-3
And lady bug Johns recipe 3-1.5-2
Soil PH around 5.5 to 6.

Worth

[Hellmanns]

Originally Posted by Worth1

I totally agree.

I fertilize with something that is higher in N than anything else.
Best year ever.

Plant tone. 5-3-3
And lady bug Johns recipe 3-1.5-2
Soil PH around 5.5 to 6.

Worth

That's right, Worth, N promotes growth, without growth there will be no flowering or fruit set.

If the top of the tomato plant is not tender and showing new growth, it's a no brainer....it needs N!

[Gardeneer]

Originally Posted by Worth1

I totally agree.

I fertilize with something that is higher in N than anything else.
Best year ever.

Plant tone. 5-3-3
And lady bug Johns recipe 3-1.5-2
Soil PH around 5.5 to 6.

Worth

Worth, How come ?!
I though you are a TTF fan 3.1 . 3.8 . 7 ??

But I make my own blend :
mix 50/50 MG 12-4-8 and Alaska 0-10 -10 .
You will end up with 6 - 7 - 9 . PERFECT TOMATO FERT. Even better than TTF

[Worth1]

Originally Posted by Gardeneer

Worth, How come ?!
I though you are a TTF fan 3.1 . 3.8 . 7 ??

But I make my own blend :
mix 50/50 MG 12-4-8 and Alaska 0-10 -10 .
You will end up with 6 - 7 - 9 . PERFECT TOMATO FERT. Even better than TTF

I cant get the stuff here without ordering it.
That is stupid the guy is only about 150 miles from me.
I used to live there.

Worth

[Lindalana]

mmm, Brandywine yellow is way late on a good year and with proper planting in my experience. Like it but poor producer and late for my zone.

[amideutch]

From the Aggie-horticulture web site.

Several conditions can cause tomatoes to not set fruit. Too much nitrogen fertilizer, nighttime temperatures over 70 degrees F., low temperatures below 50 degrees F., irregular watering, insects such as thrips or planting the wrong variety may result in poor fruit set. Any of these conditions can cause poor fruit set, but combinations can cause failures. If Extension recommended varieties are used , the main reason tomato plants do not set fruit is because they are not planted where they can receive 8-10 hours of direct sunlight daily. Any less direct sunlight will result in a spindly growing, nonproductive plant with healthy foliage.

Ami

[zipcode]

A foliar of Boron and a bit of normal fertilizer like 2-1-3. Boron is really important for flowers setting the fruit.

[ScottinAtlanta]

Someone here recommended Alaska Morbloom Concentrate 0-10-10 Fertilizer,

I am trying it, and it seems to be working well even in the Georgia heat.

[bower]

I overlooked your comment about shade, and Ami is right, that's an important cause of plants with nice foliage but no fruit. It's variety specific IME, some are more 'shade tolerant' than others, some are super shade intolerant and won't set at all without lots of sun. Fertilizer won't help if that's the case. You may get a few fruit by pruning them back severely.